Rat-hole drilling attachment for rotary drilling rigs



March 23, 1943.

E. L. ALEXANDER ET AL RAT-HOLE DRILLING ATTACHMENT FOR ROTARY DRILLING RIGS Filed Jan. 9, 1941 2 Sheets-Sheet 1 .7? fil go 10 3 ,5 2' I? I 50 l6 14 43 3- ,2 3 & I 20 2e 2 45 j; I I II I, 4 89 :5

INVE TORS Emmeff Lee lam/14 ATTORNEY March 23, 1943. 1 ALEXANDER E AL 2,314,323

RAT-HOLE DRILLING ATTACHMENT FOR ROTARY DRILLING RIGS Filed Jan. 9, 1941 2 Sheets-Sheet 2 ATTORNEY ItAT HOLE DREIJNG'AT'IACHMENTFOR ao'mnrnmmo'mos ing the rotary at the desired angle. In' accomplishing these and other objectso the invention,.as hereinafter pointed out, we

Patented Mar. 23, 1943 B OFFICE;

, u Emmett LeeAlesander than w. ninth-.1" waite, Enid, kla.,, l The-Geo!" rationof Oklahoma I: I Application larlythose of rotary type which-include a rotary table adapted torotate the Kelly rod of. a drilling string while-it is suspending'ly supported from a derrick orimast. r

It is customary practice when-rigging up an apparatus of this character, preparatory to drilling a well, to bore a slantingfrat-hole in oflset additional joints of pipe are to be added thereto.

' It is-a principal object of the-presentinven- -tion-to facilitate drilling of the -=rat-hole by providing anrotary drilling rig with an attachment whereby the rat-hole may be boredby the rotary mechanism utilizing the power of 'the drillingrigp It is also an object of the invention to provide a simpleand readily portable support forcarr'yhave provided improved structure,' the preferred form of-which is illustrated in the accompanying drawings, wherein: I

Fig.- 1 is a perspective view of a drilling rig equipped with an attachment embodying the features of the present invention. v

. Fig. 2'is a plan view-of the rig and attachment,

January 9, 1

. r (Cl.255-"--1 9) This-invention relates to'drilling rigs, particuthe legs of the derrick being shown in horizontal section.- r r 4 Fig. 3 is a side elevational view of the'mechanism shown in Fig. 2.

.. Fig.- 4 is a detailview of the; swivel bearing forsupporting the'drive shaft connection.

Referring more in detail to the drawings-2' v l designates a drilling rig which, in the illus- -tration", is of portablecharacter, and includes,

a-main platform" 2 carried on the chassis 3 of a motor've h-icle, indicated by the wheels 4. ,Pivotallymounted on standards 5 and 6, near the rear ofthe platform, is a'derrick ormast 1, arranged to 'be'moved from "a horizontal transport position' to" a'perpendicular ordrilling position with thefforit'legs 8 thereof supported on the platform. f-The derrick is moved to and from drilling pz'z'sitic'niflzlytelescoping hydraulic cylinders 9 and The" drillingr'ig includes a turntable II including a base 'plati'e l2, and" a j gear housing I 3 carrying a r ng gear H which is driven by a pinionge'ar' 'lij'fixed to ajdrive shaft'lli, the drive shaft l6 being mounted in a lateral extension of the gear housing. The turntable 11' carries a drive bushing I! for rotating the Kelly rod l8 During drilling operations'the rotary turntable is mounted over an opening IS in the rear of the platform, in alignment with the crown pulley (notishown) of thederrick, and the shaft I6 is Failing Supply Company, Enid, Okla... 21. ,corpo-j 941, Serial No. 373,774.

"connected with the driving shaft 20 of a drawworks 2!, also mounted on the platform and forwardly of the derrick, the shafts being connected by a telescoping drive-"including a tubular section 22- in which is slidably secured a splined section 23; The section 23 is connected withthe shaft 20' by a universaljoint 24, and

the tubular section 22 is connected with the 'shaft l6 by auniversal' Joint 25 and 'fla'nge couplings 26 and 21,- one of which is fixed directly on" the shaft l6 and the other forms-apart of the universal joint 25. The -telescoping 'shaft and universal jolnt'connection allow'for any misalignment occurring between the rotary and the power shaft 20; and compensate for any torsional movementthat' may be produced in the platform. The turntable II 'when in drilling position, is secured to the platform by 'suitable fastening devices, such as bolts 28, extended through openings 29 in the corners ofthe plate "I2 and into thestructural members of the platform 2 When the turntableisin this position, the flanges 26 and 2l' arejsecured together by removable fastening devices, 51101188 bolts 30, so

that rotation of thepower shaft Zleffe'cts rotation In rigging up a drilling rig at a location where a well is to be drilled, it is the practice .to bore a rat-hole" in 'ofisetv relation with the well hole to bexdrilled, andthe offset, hole is cased to provide apocket for accommodating the drilling rod while the travellingblock-isbeing used to operate 'the elevator when adding sections of pipeto the drilling string, orfwhen th'edrill pipe is being runlinto or removed from thei'well. Usuallythe rat-hole" is drilled by rotating the Kelly rod by hand. Both methods require .con9

siderable time and labor, and delay beginning of the'drilling operation. As above pointedout, it is the principal object oftheprese'nt inven-; tion to "providefthe derrick with 'an attachment edge to edge relation.

two rows of horses ll and 42, arranged to support pairs of sills 4345 and H8 extending longitudinally of the platform 2, the bases 41 of the horses being supported on longitudinal sills 48 placed on the ground so that cross-bars 49 of the horses are in alignment to support the pairs of sills |3 and "H6. Mounted on the longitudinal sills are platform boards 50 placed in The supplementary platform thus provides a support for the turntable over the site of the rat-hole. The rotary, upon being removed from the derrick platform, is supported on a sub-plate which is blocked up at the desired angle on the platform by blocks- 52 so that it slopes toward the longitudinal center line of the drilling rig and in the direction of the derrick. The rotary table, after being mounted thereon, is connected with the power shaft 20 by means of ashaft extension 53, having a flange coupling 54 atone end corresponding to the-flange coupling 26 of the rotary and secured to the flange coupling 21 as shown in Fig. 2. The other end of the shaft 5 carries a universal joint 55, having a flange 55 corresponding with the flange 21 and-which is connected with the flange 26 of the rotary by the fastening devices 30, as shown in Fig. 2

Supported on the derrick platform is a channel 51, having an opening 58 in its upper flange and a socket 59 carried by its lower flange to accommodate a swivel pin 60 carrying a yoke 61. Tnmnioned between the arms of the yoke, on pins 62, is a bearing sleeve 63, arranged to pass the shaft 53 as shown in Figs. 2, 3 and 4. i

In erectingthe attachment to drill the rathole," the sills 48 are placed on the ground to support the'horses I, after which the longitudinal sills 43-44 and 4545 are mounted on the horses to support the platform boards 50. The fastening devices 30 securing the coupling members 25 and 21, and the bolts 28, are removed, whereupon the entire rotary is shifted onto the plate II which has been tilted at the desired angle by the blocks 52 to support the rotary in an inclined position. The shaft extension 53 is then inserted between the flange couplings 26 and desire to-secure by Letters including a main platform and a turntable mounted thereon, an attachment for boring a rat-hole including a supplementary support offset and and 21 with the pin passing through the opening 58 and entering the sockets 59. The flange V the earth and forms the rat-hole at the angle at which the rotary is supported. When the "rat-hole has been drilled to the desired depth, the draw-works is'operated to raise the kelly and bit through the table, after which the shaft extension is removediand the table returned to its original position on the derrick platform so that it may be secured by the fastening devices 28 and the shaft coupling 28 connected with the coupling 21. The "rat-hole" may then be cased so as to receive the Kelly rod when the bail of the swivel is to be disconnected from the safety hook of the travelling block. If desired, all or part of the platform extension may be left in position to extend the working space about the derrick.

separate from the platform and onto which the turntable is adapted to be moved to borea rathole, a driving means on the main platform for driving the turntable when the turntable is in position on the main platform, a flexible extension having coupling means to connect with said driving means and having means for connection with the turntable when the turntable is mounted on the supplementary support, a bearing for rotatably mounting the shaft extension, and means forpivotally and swivelly mounting the bearing on one of said platforms.

2. ,In combination with a portable drilling rig including a main platform having a draw-works,

a turntable mounted on said main platform, a drive shaft, a universal Joint. connecting the drive shaft with the draw-works and a universal Joint connecting the drive shaft with the turntable, an attachment for drilling a rat-hole including a supplementary platform offset from the main platform and adapted to support said turntable, -a drive shaft extension having coupling means for connection with the universal joint which connects with the turntable when the turntable is positioned on the main platform, a universal Joint at the opposite end of the shaft extension, a coupling connecting said last named universal Jointwith the turntable when the turntable is mounted on said supplementary platform, a bearing on the main platform .Journalling one of said shafts adjacent the universal joint which connects the drive shaft with the drive shaft extension, and means swivelly mounting the bearing relative to the main platform. v

3. In combination with a portable drilling rig including a main platform having a draw-works, a turntable mounted on said main platform, a drive shaft, a universal Joint connecting the drive shaft with the draw-works and a universal joint connecting the drive shaft with the rotary table, anattachment for drilling a rat-hole including a supplementary platform offset from the main platform and adapted to support said turntable, a drive shaft extension having coupling means at one end for connection with the universal joint which connects with the turntable when the turntable is positioned on themain platform,- a universal joint at the opposite end of the shaft extension, a coupling connecting said last named universal Joint with the tumtable when the turntable is mounted on said supplementary platform, a bearing on themain platform and Journalling one of said shafts adiacent the universal joint connecting the drive shaft with the drive shaft extension, and means pivotally and swivelly mounting the bearing relative to the main platform.

EMME'I'I' LEE ALEXANDER. ALBERT w. BRAITHWAITE. 

